1. Field of the Invention
A targeting jig apparatus for targeting interlocking holes of an intramedullary nail.
2. Description of the Prior Art
It is well known in the art to use intramedullary nails to stabilize bone fractures. The intramedullary nail is inserted into the medullary canal of the bone across the fracture site in order to align the bone fragments with one another and prevent the bone fragments from being displaced during healing. The intramedullary nail typically includes interlocking through holes at the distal and proximal ends of the nail that are in alignment with holes drilled into the bone of the patient. Tightening screws are threaded through the holes in the bone of the patient and pass through the interlocking holes to hold the bone fragments in place. A common difficulty in the art relates to locating a bone drill-guide with the interlocking holes in the intramedullary nail, particularly at the end of the nail remote to the incision and after implantation into the bone of the patient.
Adjustable targeting jigs are well known in the art for locating the bone drill-guide with the interlocking holes in the nail prior to implantation of the intramedullary nail, such that after implantation the holes are located. One such adjustable jig is disclosed in U.S. Pat. No. 4,667,664 and includes a support-arm extending along a support-arm axis from a support-arm proximal end to a support-arm distal end and spaced from and substantially parallel to the intramedullary nail. A targeting mechanism is disposed on the support-arm for adjustment of the targeting mechanism relative to the support-arm and defining a targeting mechanism drill-guide orifice for aligning the targeting mechanism drill-guide orifice with one of the interlocking holes of the intramedullary nail.
Known problems with the current art are that the means for adjustment of the targeting jig are generally complicated leading to increased costs and difficulties in use.